Relay



March 2, 1943.

c. N. HICKMAN EI'AL 2,312,902

RELAY Filed Nov. 27, 19.40 2 Sheets-Sheet 2 .c. /v. H/CKMAN ATITORNEVPatented Mar. 2, 1943 UNITED STATES PATENT OF'FlCE RELAY ApplicationNovember 27, 1940, Serial No. 367,339

*l'v Claims.

This invention relates to electromagnetic devices and more particularlyto relays.

Relays used as line relays in telephone systems of the cross-bar typeare customarily mounted in groups of ten, each relay having two pairs ofcontact springs. One spring of each pair is connected to the groundedterminal of the central ofiice battery, the other spring of one pair isconnected to a circuit individual to the line with which the relay isassociated and the other spring of the other pair is connected to acircuit which is common to ten lines. It is thus apparent that upon theinstallation of such a group of ten-line relays it is necessary toconnect three springs of each relay in multiple-with the correspondingspings of the other relays of the group of ten relays thus requiringthirty soldering operations. A consideration of these requirements hasled to the conclusion that a considerable simplification of thestructure and installation of relays of this type might be achieved.

It is therefore the object of the present invention to simplify themanufacturing and assembling of relays of the type above discussed.

In accordance with the present invention this object is attained byeliminating the usual contact springs and by so constructing themagnetic circuit of the relay that the required circuit paths may beestablished entirely through the conductive engagement of a single reedtypearmature with a divided core. The magnetic-circuit of the relaycomprises two parallelly disposed cores positioned out of contact witheach other and having out-turned po1e-piece-ends,-a fiat reed typearmature and a cylindrical heel-piece interposed between the rear endsof the cores and the rear end of the armatures. The armature-is inengagement with oneend of the heel-piece but the cores are electricallyinsulated from the other end ofthe heel-piece by an-interposed strip ofinsulating material. The reed armature is slotted to form two armaturesections and each such section is bifurcated to formtwo contact prongs,the armature sections cooperating respectively with the pole-piece endsofthe-two cores and being separatedtherefrom by suitably. adjustedair-gaps. The energizing coil surrounds both cores and a forwardlyextending portion of the insulating strip, the forward end of. suchstrip having a lug extending between the out-turned pole-pieces of thecores to'maintain them out of contact with each other.

The rear spoolhead of the energizing coil has two parallellydisposedwinding terminal 1 lugs, Which also-serve as soldering terminals,riveted thereto by eyelets formed integrally with such terminals. Theseterminal lugs extend rearwardly parallel to the two cores and areseparated from such cores-byan interposed strip of insulating material.These relay elements are clamped together between a mounting bracketwhich is in conductive engagement with the armature reed and a clampingwasher insulated from the coil terminal lugs by an interposed insulatingwasher by a screw which extends through holes in the clamping washer, inthe insulating washer, in the heelrpiece, in the armature and into athreaded hole in the bracket. To assure that the rear ends of the coresare suitably insulated from each other and fromtheclamping screw andthat the coil terminal lugs are also insulated from each other .and fromthe clamping screw, the screw is surroundedby a bushing of insulatingmaterial where it passes between the rear ends of the .cores and betweenthe rear ends of the terminal lugs.

It is proposed to mount these relays close together in groups of fiveor. more on a relay mounting plate. .When: thus mounted all of the relayarmatures will be conductively connected to the mounting'plate which.isin turn connected to thegroundbus=bar and one core of each relay willbe connectedto acommon circuit multiple. Thus when the. coil of. anyrelay isenergized, the engagement of the reed armature with the twocores thereof willconnect ground to the common circuit multiple and willalso connect groundto the other core which is connected to a circuitindividual to such relay.

To prevent the creation of stray magnetic fields which might hinder theoperation of adjacent relays when one relay vof the group is operated,the relay. cores are given a reduced cross-section at the portionsthereof which are enclosed by thevrelay coil to concentrate the magneticflux. Inaddition, if found desirable the dust cover which covers thevgroup of relays maybe made of magnetic material and provided withpartitions interposed between adjacent relays, or the mounting bracketof each relay may be extended forwardly to provide a magnetic shieldwhich is interposed between the magnetic circuits of adjacent relays.

To improve the releasing characteristic of the relay one of thebifurcated sections of the reed armature may be bent so that its prongslie in a plane slightlyin advance of the plane of the prongs of theother bifurcated section.

Having briefly outlined the novel features and construction of theimproved relay, reference may now be had for a more completeunderstanding of the invention to the following detailed descriptiontaken in connection with the accompanying drawings, in which:

Fig. 1 is a perspective view of an assembled group of relays constructedin accordance with the present invention together with the associatedshielding cover, such cover being broken away to better disclose two ofthe relays;

Fig. 2 is a side View of the improved relay;

Fig. 3 is a bottom view of the relay disclosed in Fig. 2;

Fig. 4 is a front end View of the relay;

Fig. 5 is a detail view of one of the coil terminal lugs of the relay;

Fig. 6 is a perspective exploded View of the relay parts; and V Fig. 7is a bottom view of the relay equipped with a mounting bracket modifiedto also serve as a shielding member.

Referring first to Fig. 1, an assembly of relays is disclosed eachsecured by its mounting bracket l and a screw 2 to a U-shaped mountingplate 3 which may be secured in any desired manner to a relay orapparatus rack. The out-turned arms 4 of the plate 3 serve as guides fora relay cover 5 which, when in positon over the guide arms, effectivelyencloses the relays. The cover 5 may be made of magnetic material forthe purpose of introducing a shield between the assembly of relays andadjacent relay assemblies. In order to provide shielding between theadjacent relays of the assembly, the cover 5 may be provided withpartitions 6 of magnetic material secured between the parallel top andbottom walls 1 and 8 by cars 9 which are formed on the top and bottomedges of the partition, are inserted through slots in in the walls andare then bent over on the outside of such walls. To permit the solderingterminal lugs of the relays to extend towards the wiring side of themounting plate 3 such plate is provided with a notch H adjacent to eachrelay. While, for convenience, the relay assembly has been illustratedas in a vertical position in Fig. 1, it is to be understood that itwould be installed in a horizontal position, that is, with the wall 7 ofcover 5 uppermost and lying in a horizontal plane.

Each relay of the assembly comprises two cores l2 and I3 stamped from asheet of magnetic material into the shape best disclosed in Fig. 6 Thecore 12 has its forward end bent laterally at right angles and thenoutwardly to form a pole-piece M upon the pole-face of which twocontacts l5 are welded or otherwise secured, has the portion thereoflying within the relay coil 28 reduced in cross-section as indicated at56 for the purpose of concentrating the lines of flux generated upon theenergization of the coil, has the inside edge of its rear portionarcuately notched as indicated at i! for the reception of the insulatingbushing or sleeve i8 as will be later described and has its rear portionnarrowed and thinned to form a soldering terminal is. The other core I3similarly has it forward end bent laterally at right angles and thenoutwardly to form a pole-piece 20 upon the pole-face of which twocontacts 2| are welded or otherwise secured, has the portion thereoflying within the relay coil reduced in cross-section as indicated at 22,has the inside edge of its rear portion arcuately notched as indicatedat 23 and has its rear portion narrowed and thinned to form a solderingterminal 24.

Positioned adjacent to one face of the cores i2 and I3 is a strip 25stamped from a sheet of suitable insulating material, such as hardrubber or fiber. The strip 25 has its forward end narrowed sufiicientlyfor insertion through the relay coil, is provided on its forward endwith a lug portion 25 which enters between the laterally bent endportions of the cores l2 and I3 to hold such cores spaced out ofconductive engagement, is provided with a hole 21 in the center of itsrear end portion for the reception of a clamping screw t9 as laterdescribed and is provided with a notch iii in its rear end to receive alocking lug 52 of the bracket l.

A coil 28 having a rear spoolhead is provided with a central rectangularopenin therethrough for the reception of the cores E2 and I3 and theinsulating strip Riveted to the rear face of the spoolhead 29 are two L-shaped terminal lugs 3! and 32. Lug 35 is disclosed in perspective inFig. 5 and comprises a short arm 33 having two parallelly disposedeyelet portions 34 pressed therein and a long arm terminating in asoldering terminal. The long rm is provided with an arcuate notch 35 inits inner edge for the reception of the insulating bushing l8. Lug 32 issimilar to lug 35 but the notch 36 and soldering terminal thereof arereversely positioned as more clearly disclosed in Fig. 6. a

The relay armature 31 is stamped from a sheet of magnetic material andcomprises a wide rear clamping section 38 having a hole 39 therein forthe reception of the clamping screw 49 as will be later described, anarrow portion 40 for rendering the armature more resilient and forcausing a concentration of the lines of force and a widened and slottedforward end portion. The central long slot 6| divides the forward end ofthe reed armature into two magnetic sections each of sufiicient width tocooperate with the pole-piece of one of the cores and the shorter slots42 and 43 further bifurcate the two sections to form contact carryingprongs each provided with a contact 44 welded or otherwise secured tothe inner surface thereof. These contacts are so positioned that two ofthem cooperate with the two contacts I5 carried by the pole-piece M ofcore 12 and the other two of them cooperate with the two contacts 2%carried by the polepiece 20 of core l3.

For suitably spacing the armature reed 31 from the cores [2 and I3 atthe rear end of the relay structure and for completing the magneticcircuit a cylindrical heel-piece 45 of magnetic material is provided forinsertion between the armature and the strip 25.

In assembling the relay the cores l2 and |3are first assembled side byside in the position disclosed in Fig. 6 and are then pushed rearwardlythrough the opening 30 in the coil 28. The insulating strip 46 is theninserted between the rear ends of the cores l2 and I3 and the coilterminal lugs 3| and 32 with the hole therein in alignment with thearcuate notches in the inner edges of the cores and terminal lugs. Thereduced portion of the insulating strip 25 is" then pushed forwardlythrough the opening in the coil 28 until its outer end abuts the rearfaces of the lateraly bent portions of the cores l2 and I3 and its lugportion 26 ispositionedbetween the inner edgesof such bent portions. Thecylindrical heel-piece 45 is then mounted on the exposed face of thestrip 25 withthe axial hole thereof in alignment with thehole 21 in thestrip 2-5. ThearmatureB'I-is then positioned on the exposed end of theheel-piece 45 with the hole 39 therein aligned with the axial holethrough the heel-piece and the angular mounting and clamping bracket isthen positioned outside the armature with the threaded hole 41 thereinin alignment with the hole 39 in the armature with the end of thearmature engaged in the inner angle of the bracket and the lug 52engaged lin the notch in the end of strip 25. The washer 48 is thenpositioned in engagement with the outer faces of the terminal lugs 3|,32 with the hole therein in alignment with the hole in strip 46 andinsulating bushing H3 is then inserted through the holes in the washer48 and strip 46 and through the circular spaces defined by the arcuatenotches and 36 in the terminal lugs 3| and 32 and by the arcuate notchesl1 and 23 in the cores l2 and I3. The bushing l8 then serves to hold theparallel terminal lugs 3| and 32 in spaced relationship and the rear endof the cores also in spaced relationship and insulated from the clampingscrew 49 which, when inserted through the hole in the clamping washer53, through the bushing l8, through the holes in the strip 25,heel-piece and armature 3 and threaded into the threaded hole 41 in thebracket clamps the several members together. It will be noted that whenthe relay has been thus assembled the engagement of the end of thearmature within the inner angle of the bracket and the engagement of thelug 52 of the bracket in the notch 5| of the insulating strip 25 holdsthe armature in proper alignment with the polepieces I4 and 20 of thecores l2 and I3.

After the relay has been thus assembled, the reed armature may be bentas required to secure the proper air-gaps between the prongs thereof andthe pole-pieces of the cores l2 and I3 and to insure that the relayarmature will release quickly. The plane of the two contact prongs ofthe armature which cooperate with the polepiece of one of the cores maybe displaced relative to the plane of the other two contact prongswhereby when the armature is attracted to engage all contact prongs withthe pole-pieces of the cores the two contact prongs which have beendisplaced ahead of the other two will be under slightly greater tensionthan the other two and will therefore tend to accelerate the release ofthe armature when the strength of the energizing current flowing throughthe coil 28 falls below a predetermined holding value. It is to be notedhowever that even with the contact prongs thus bent, the two sections ofthe armature formed by the central slot 4| will both be attracted intocontact engagement with their associated core pole-pieces by the samevalue of operating current thus insuring that when the energizingcurrent in the coil 28 is strong enough to engage the contacts 4| of onearmature section with contacts |5 on core l2, the contacts 4| of theother armature section will also engage with contacts 2| on core [3.

As hereinbefore stated, the magnetic crossfire between adjacent relaysof the assembly may be materially reduced by the provision of the covershield 5 having the partition 6. The same result may be secured by theuse of a cover shield without partitions and by the provision of amounting bracket for each relay of the type disclosed in Fig. 7. Thisbracket 53 is made of magnetic material and has a portion 54 ofrectangular shape extending forwardly to a point just beyond the forwardend of the relay. This rectangular portion is of sufiicient length andwidth to effectively fill the space between the side walls I and 8 andthe end wall of the cover 5 when such cover is in the position over therelay assembly illustrated in Fig. 1. Instead of bending the bracket asdisclosed in Fig. 7 to form a forwardly extending shield portion 54, thebracket may be of the type disclosed in Fig. 3 with a separate shieldportion welded or otherwise secured thereto.

The cross-fire may also be reduced by so connecting the battery andground wires to the coil terminal lugs 3| and 32 of the relays of anassembly group that the current flow in alternate relays will bereversed.

What is claimed is:

1. In a relay, a pair of cores disposed parallel to and out of contactwith each other, each of said cores having its forward end bentlaterally and then outwardly to form a pole-piece, a strip of insulatingmaterial disposed adjacent to said cores having a lug on its forward endengaged between said laterally bent portions of said cores to hold saidcores in spaced relationship, an energizing coil surrounding said coresand said strip, a heel-piece supported on the rear end of said strip andinsulated thereby from the rear ends of said cores, a reed armaturesupported on said heel-piece, the forward end of which is attractableinto conductive engagement with the pole-pieces of both of said cores,an insulating bushing disposed between the rear ends of said cores tohold them in spaced relationship, a clamping washer insulated from saidcores by an interposed insulating washer, a mounting bracket and a screwextending through aligned holes in said clamping washer, said bushing,said heel-piece and said reed armature into a threaded hole in saidbracket for clamping said elements together.

2. In a relay, a pair of cores disposed parallel to and out of contactwith each other, each of said cores having a portion thereof adjacentits pole-piece end reduced in cross-sectional area to cause aconcentration of flux flow therein, an energizing coil surrounding saidportions of said cores, a reed armature having its rear end supported onbut insulated from the rear end of said cores, the forward end of whichis attractable into conductive engagement with the pole-piece ends ofboth of said cores, a mounting bracket and means to secure said coresand said armature to said bracket.

3. In a relay, a pair of cores disposed parallel to and out of contactwith each other, an energizing coil surrounding said cores, a reedarmature having its rear end supported on but insulated from said coresand having its forward end slotted to form two pairs of contact carryingprongs, one pair of which is attractable into conductive engagement withthe forward end of one of said cores and the other pair of which isattractable into conductive engagement with the forward end of the otherof said cores, one pair of said prongs being bent to normally lie in aplane slightly in advance of the plane of the other pair of prongswhereby the speed of release of said armature is increased, a mountingbracket and means to secure said cores and said armature to saidbracket.

4. In a relay, a pair of cores disposed parallel to and out of contactwith each other, an energizing coil surrounding said cores, a reedarmature having its rear end supported on but insulated from the rearends of said cores, the forward end of which is attractable intoconductive engagement with the forward ends of both of said cores, amounting bracket of magnetic material having a portion thereof extendingforwardly parallel to said armature to shield it from stray magneticflux, and means to secure said cores and said armature to said bracket.

5. In a relay a core having a pole-piece on its forward end, anenergizing coil surrounding said core, an armature having its rear endsupported on the rear end of said core, the forward end of which isattractable into engagement with the pole-piece of said core, a mountingbracket of magnetic material having a portion thereof extendingforwardly parallel to said armature to shield it from stray magneticflux, and means to secure said core and said armature to said bracket.

6. In a relay, a supporting bracket, a core secured thereto, an armaturesecured to said bracket with its free end cooperating with the free end'of said core, an energizing coil supported on said core having a rearspoolhead and L- shaped coil terminal lugs having eyelets integrallyformed in their short arms extending through holes in said spoolhead andspun over on the inner surface thereof by which said lugs are secured tosaid spoolhead and having their long arms extending rearwardly from saidspoolhead and insulatedly clamped to said bracket.

'7. In a relay, a pair of cores disposed parallel to and out of contactwith each other, a reed armature having its rear end supported on butinsulated from the rear ends of said cores the forward end of which isattractable into conductive engagement with the forward ends of both ofsaid cores, an energizing coil surrounding said cores and having a rearspoolhead, two L-shaped coil terminal lugs having eyelets integrallyformed in their short arms extending through holes in said spoolhead andspun over on the inner surface thereof by which said lugs are secured tosaid spoolhead and having their long arms extending rearwardly parallelto each other and to said cores and insulated from said cores, aninsulating bushing disposed between the rear ends of said cores andbetween said lugs to hold them in spaced relationship, a clamping washerinsulated from said lugs by an interposed insulating washer, a mountingbracket and a screw extending through aligned holes in said clampingwasher, said bushing and said reed armature into a threaded hole in saidbracket for clamping said members together.

CLARENCE .N. HICKMAN. EMORY LAKATOS.

